The invention relates to an oscillator comprising a one-stage amplifier and a quartz crystal resonator which operates in series resonance to an LC oscillating circuit.
In order to produce high frequencies with the aid of quartz crystal oscillator circuits, it is known to use harmonic quartz crystals which oscillate at a specific mechanical harmonic of the oscillating quartz crystal in oscillator circuits. As quartz crystals are very difficult to produce for very high frequencies and consequently are expensive, in specific circumstances it can be more economical to use a harmonic quartz crystal with half the desired frequency and to double this frequency for example with the aid of a following multiplier stage.
A plurality of series connected stages which are each provided with an amplifier have the disadvantage, however, that this impedes an exact tuning of the oscillating circuit to the frequency which is to be produced.
If oscillators provided with oscillating quartz crystals are used for example to drive acousto-optical deflecting devices in non-mechanical high-speed printers, it is neccessary for such oscillators to be switched on and off very rapidly. Short switching times on the order of approximately 100 ns cannot be achieved, however, in known oscillator circuits having only one stage such as disclosed in Halbleiterschaltungstechnik by Tietze and Schenk, 2nd Edition, 1971, page 371.